Utilisation Des Protéines Par Le Veau Préruminant a L'engrais. Iii. — Influence Du Remplacement Des Protéines Du Lait Par Celles Du Poisson Sur La Vidange Stomacale

Circadian changes in the abomasal secretions of the preruminant calf

“…This is in agreement with other observations made in the calf which showed that the outputs of enzymes were maximal 10-20 min (Grosskopf, 1959 ;Ash, 1964) (Guilloteau et al, 1975 and1979) and the curves of enzyme secretions showed that the trends were similar. Immediately after a meal, the pH was high (about 5) so that the enzymes secreted in large quantities could exert their coagulating activity.…”

“…The variation of pH in the abomasal pouch was not representative of changes in the pH of the abomasal contents. The pH of the contents is much higher after the meal because of the dilution induced by the intake of milk and its buffering capacity (Hill, Noakes and Lowe, 1970 ;Guilloteau et al, 1975 and1979) : it ranges around 5 after the first 0.5 h, then decreases progressively, but 7 h after a meal it is still 3.5. The decrease in the pH of the gastric juice collected after the morning meal could account for the large increase in the concentration of H + + ions together with a concomitant decrease in the concentration of Na + ions which was not compensated by an increase in the concentration of K + ions.…”

Digestion des protéines du lait dans la caillette du veau préruminant. Evacuation gastrique après un repas d'épreuve

“…chez le rat (Zebrowska, 1968 ;Buraczewski et al, 19711, le porc (Braude et al, 1970 a, b) et le veau (Toullec, Thivend et Mathieu, 1971 ;Ternouth et Roy, 1973 ;Guilloteau et al, 1975Guilloteau et al, , 1979 alimentés avec du lait ou des régimes à base de caséine ou de protéines du lactosérum.…”

“…Pour mettre en évidence les effets éventuels de la matière grasse, du lactosérum, des minéraux et de la coagulation, nous avons utilisé différents régimes : lait entier, lait écrémé, lactosérum, solution de caséine dans un milieu minéral simulant le perméat de lait ultrafiltré (Jenness et Koops, 1962) Mathieu, 1971 ;Guilloteau et a/., 1975). Cela est vraisemblablement à relier au fait qu'après le repas, la motricité est désorganisée pendant un temps plus ou moins long selon l'animal ou le jour (Dardillat, 1982 (Tourneur et Lenoir, 1980).…”

Influence de la cinétique d'évacuation gastrique de l'aliment sur l'insulinémie chez le veau préruminant

“…During the first experimental period (A), group I received a control diet that contained skim-milk powder as the only protein source, whereas group 11 received an experimental diet containing fish protein concentrate as the main protein source. During the second experimental period (B), the diets were switched.It was previously shown that the rate of fat and amino acid absorption increased when milk proteins in such milk substitutes were replaced by hydrolyzed fish proteins (Guilloteau et al, 1975).The results showed that during any experimental period in the control group, there was a decrease in the postprandial blood free amino nitrogen. Blood triglycerides exhibited a small increase at 0.5 h after the meal but a large decrease at 1-4.5 h. The meal also resulted in a very large increase in blood glucose with maximal values occurring at 1-4.5 h. Blood insulin showed a large increment at 0.5 h then increased slowly, peaking at 2-3 h. The postprandial increase in blood insulin was less during the first experimental period than during the second one.…”